update caheui

[puzzlet]

There was a bug in caheui which have been fixed: aheui/caheui#9

To elaborate, the interpreter would fall itself in an index-out-of-bound error when it runs a certain code. (i.e. ㅆ instruction to move data to the same place.)

This is one of most hardly used feature of the language -- I don't think anyone had come up to exploit this yet. So I guess it's safe to patch the interpreter.